1. Field
Apparatuses consistent with exemplary embodiments relate to an image sensor including a color separation element, and more particularly, to an image sensor capable of improving the efficiency of using light by using a color separation element.
2. Description of the Related Art
In general, a color display device or a color image sensor displays an image of various colors or sense colors of incident light by using color filters. In the existing color display devices or color image sensors, a red, green and blue (RGB) color filter method is widely used. According to this method, a green filter, for example, is located on two pixels among four pixels and a blue filter and a red filter are respectively located on the other two pixels. In addition to the RGB color filter method, a cyan, yellow, green and magenta (CYGM) color filter may be employed. In this case, color filters corresponding to cyan, yellow, green, and magenta, which complement each other, are respectively located on four pixels.
However, the efficiency of using light may be low since each of color filters absorbs lights of colors except for a particular color allowed to transmit each color filter. For example, when an RGB color filter is used, only one-third of incident light is transmitted and the other two-thirds of the incident light are absorbed. Thus, the efficiency of using the incident light is only about 33%. Thus, a large amount of light is lost when a color filter is used in a color display device or a color image sensor.
Recently, in order to increase the efficiency of using light in a color display device or a color image sensor, various attempts have been made to use a color separation element instead of the color filter. The color separation element may separate the colors of incident light based on the diffraction or refraction characteristics of light which vary according to the wavelength thereof. The colors separated by the color separation element may be provided to pixels corresponding to the colors.